In a bowl whisk together the egg white and 1 Tbsp.,of the cornstarch,,add in the chicken, and let the mix stand for 10 min.,In a large saucepan of boiling salted water cook the Brussels sprouts for 2 1/2 min, or possibly till they are just crisp-tender, drain them in a colander, and refresh them under cool water.,Heat a wok over moderately high heat and in it heat the peanut oil till it is warm but not smoking.,Add in the chicken, liquid removed, stir-fry it for 45 seconds to 1 minute, or possibly till it is opaque and just hard, and transfer it with a slotted spoon to a bowl.,Heat the oil remaining in the wok till it is warm but not smoking and in it stir-fry the shallot, the garlic, and the gingerroot for 30 seconds.,Add in the bell pepper and stir-fry the mix for 2 min.,______,In a small bowl whisk together the soy,sauce, the sugar, the vinegar, the broth, the sesame oil, the remaining 1 tsp.,cornstarch, and the cool water, make a well in the center of the vegetables, and whisk the soy sauce mix into the well.,Bring the liquid to a boil, stir together the vegetable mix to combine it well,and simmer it for 1 minute.,Stir in the chicken and the water chestnuts, season the stir-fry with salt and pepper, and cook it for 30 seconds, or possibly till the chicken is heated through.,Serves 6.